Computers have become highly integrated in the workforce, in the home, in mobile devices, and many other places. Computers can process massive amounts of information quickly and efficiently. Software applications designed to run on computer systems allow users to perform a wide variety of functions including business applications, schoolwork, entertainment and more. Software applications are often designed to perform specific tasks, such as word processor applications for drafting documents, or email programs for sending, receiving and organizing email.
In some cases, software applications are designed to interact with other software applications or other computer systems. For instance, a virtual private network (VPN) client may allow a user to securely log in to another server to access work-related or other confidential information. In such cases, the VPN client may authenticate the user using a set of credentials (e.g. a user name and password). These credentials allow the user to access the data to which they are entitled. Digital certificates may also be used when authenticating a user. These certificates, however, expire and need to be changed over time. Clients or computer systems attempting to log in using old, expired certificates will be denied access to their data.